The Clalit Research Institute is currently examining the effect of the vaccine against the coronavirus  developed by Pfizer. 

Preliminary data show that 14 days after the injection of the first vaccine, there is a real decrease in the rate of infection in the corona .

The study compared the infection data of about 200,000 people aged 60 and over who were not vaccinated with the infection data of about 200,000 vaccinators of the same age group who are generally insured and who were monitored for at least 11 days from the date of first vaccination.

What happens in the first week after receiving the first dose of the corona vaccine?

The study showed that between the fifth day and the 12th day after receiving the first vaccine dose, there were no differences between the vaccinated group and the non-vaccinated group: the rate of positive tests for the corona virus in the two groups was similar. In other words, no difference in infection rates was observed between those who were vaccinated and those who were not vaccinated.

This finding is consistent with what the vaccine manufacturer , Pfizer, said, in which the vaccine effect should not be expected for the first 12 days after receiving the vaccine.

Two weeks after receiving the first vaccine dose: a decrease in the rate of infection

Among vaccinators, on the 14th day of receiving the first dose of the vaccine, there was a significant decrease – of about 33% – in the rate of positive tests for the corona virus.

Between the 15th and 17th day after receiving the first dose, the numbers remained the same: a decrease of about 20% to 40% in the rate of positive tests for Corona.

Important Information

These results clearly show that there is no complete protection against corona infection – not even after 17 days of receiving the first vaccine. Therefore, even those who have been vaccinated must  wear masks in the public space and observe the rules of social distance .

It should be emphasized: these are only preliminary results of the study that focused on those aged 60 and over. This study has not yet been peer-reviewed. Clalit’s research institute continues to monitor the results and the findings.

It should be noted that Clalit’s study identified those infected in Corona according to laboratory tests of those who chose to be tested, while Pfizer’s study referred to the appearance of a disease with symptoms.